Mailbox doesn't exist (virtual mailboxes)

[Sun Advocate Webmaster]

Okay... I have my virtual domains working properly. Now I'm having 
another problem.

When checking mail from thunderbird, I am told "error from server: 
mailbox doesn't exist."

In cyradm, 'lm' shows 'user at domain.com (\HasNoChildren)'.  I can verify 
via 'imtest' that the credentials I'm using are correct. What can cause 
this?

I haven't configured postfix yet, but I wouldn't think that is the problem.

Any help would be most appreciated, as this is my first real attempt 
toward setting up mail on linux. I'm not a linux newbie, but I am new to 
linux mail systems.

Thanks!
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